You're focusing too much on the installation process, if installing Arch was the whole of the problem things like Endeavor would be a good recommendation for newbies, but they're not. Arch has one giant flaw when it comes to being beginner friendly, and it's part of what makes it desirable for lots of us, and that is the bleeding edge rolling release model. As a newcomer you probably want something that works and is stable. Arch is not, and will never be, that, because the core philosophy is to be bleeding edge rolling release. If you're a newcomer who WANTS to have that and doesn't mind the learning curve then go ahead, but Linux has enough of a learning curve already, so it's better to get people started with something they can rely on and afterwards they can move to other stuff that might have different advantages/disadvantages.
We're talking about the general case here, I've recommend Arch to a newcomer in the past, he was very keen on learning and was happy with reading wikis to get there stuff sorted, but realistically most people who're learning a whole new OS don't want to ask questions and be told RTFM, and RTFM is core to the Arch philosophy.